COMPLEX-FORMATION IN THE SODIUM DODECYL-S ULFATE CHITOSAN SYSTEM

The regularities of the reaction between chitosan and anionic surfacta nt (sodium dodecyl sulfate) were studied in an acetate buffet solution (pH 3.5, ionic strength 0.05 mol/l) and the HCl solutions, The condit ions of phase separation in this system were determined. The soluble n onstoichiometric dodecyl sulfate salts of chitosan (the surfactant-pol yelectrolyte complexes) are formed at concentrations of the components less than 10(-4) mol/l and at the molar ratio surfactant : polyelectr olyte Z < 0.1. Such hydrophobization of chitosan leads to significant nonadditive enhancement of its surface activity. The insoluble complex es are formed at large values of Z. These complexes are additionally s tabilized by hydrophobic interactions between the alkyl radicals of bo und surfactant molecules and have almost stoichiometric composition.